1. Field of the Invention
The present invention relates to a reinforcement member for the reinforcement of concrete structures and to a method and a device for manufacturing this reinforcement member.
It applies in particular to the manufacture of reinforced-concrete slabs or panels intended for the construction of road pavements or runways, especially for motorways.
2. Discussion of the Background
A reinforcement member for reinforced-concrete slabs intended for the manufacture of road pavements, comprising a relatively narrow steel tape of small thickness, the faces of which are goffered or corrugated, is already known in the state of the art, especially from FR-A-2,579,651.
The goffering includes reliefs constituted, alternately, by projections delimiting bumps and by hollows delimiting cavities.
This type of goffering makes it possible to obtain good anchoring of the steel tape in the concrete, the effect of which is an almost complete mobilization of the strength of the reinforcement member, this being so if the concrete used has a very high strength and that the relative movements between the steel and the concrete, when a tensile force is being exerted on this tape, are greater than one millimeter.
On the other hand, when a steel tape possessing the aforementioned type of goffering is embedded in plain or lean concrete, it is found that, under the effect of a tensile force exerted on this tape, complete mobilization of the strength of the reinforcement member due to its anchoring in the concrete occurs only progressively and remains incomplete for relative movements between the steel and the concrete or the order of one quarter of a millimeter.
Now, in the case of structures such as reinforced-concrete road pavements, significant mobilization of the strength of the steel tapes is generally required for relative movements between the steel and the concrete which remain less than one quarter of a millimeter.
Moreover, the reinforcement tapes are generally packaged as reels so that, at the time they are used, the unreeled tapes exhibit a remanent or residual curvature which is very irksome when laying these tapes for the manufacture of reinforced-concrete structures.